Circuit breaker



May 29, 1951 J. A. HERRMANN Er Al. 2,555,035

CIRCUIT BREAKER Filed Aug. 6, 1948 8 Sheets-Sheet l CID `M4 MM @mmv May 29, 1951 J. A. HERRMANN r-:T AL 2,555,035

CIRCUIT BREAKER Filed Aug. 6. 1948 8 Sheets--Sheei'I 2 [www May 29, 1951A. J. A. HERRMANN ET AL 2,555,035

i CIRCUIT BREAKER Filed Aug. 6. 1948A 8 Sheets-Sheet 5 May 29, 1951 J. A. HRRMANN Er Al. 2,555,035 I CIRCUIT BREAKER 8 Shets-Sheet 4 Filed Aug. 6, 1948 loa INVENTORS` ifr- May 29, 195l J. A. HERRMANN ET AL 2,555,035

CIRCUIT BREAKER 8 Sheets-Sheet 5 Filed Aug. 6. 1948 INVENTORS.

May 29, 1951 J. A. HERRMANN Er AL 2,555,035

CIRCUIT BREAKER Filed Aug. 6, 1948 8 Sheets-Sheet 6 O Q. N

NVENTOR May 29, 1951 J. A. HERRMANN ET Al. 2,555,035

CIRCUIT BREAKER Filed Aug'. 6. 1948 8 Sheets-Sheet '7 INVENTORJ ,40M .ff. M18 mw May 29, 1951 CIRCUIT BREAKER 8 Sheets-Sheet 8 Filed Aug. 6. 1948 uN/1 mwN @QN l j 'QAM-mwa.

Patented May 29,. 1.951

CIRCUIT BREAKER John A. Herrmann and Elwood T. Platz, Detroit, Mich., assignors to BullDog Electric Products Company, Detroit, Mich., a corporation of West Virginia Application August 6, 1948, Serial No. 42,954

22 Claims. 1

ThisI application relates to circuit breakers and particularly to circuit breakers which are manually operable by an actuator or handle connected to a contactor for opening and closing the circuit and which are automatically openable upon the automatic release of a latch which normally holds and inhibits opening movement except when moved manually, as by movement of the handle.

A principal object of the present invention is to provide a novel control arrangement for interconnecting the latch, on the one hand, with the handle-contactor assembly, on the other hand, in a circuit breaker.

The control arrangement herein disclosed comprises two oppositely toothed members, one of which forms part of the handle-contactor assembly and the other of which is releasably held by the latch. The interaction of the facing teeth of these members controls the operation of the breaker.

For an understanding of the breaker herein disclosed, reference should be had to the appended drawings.

In these drawings,

Fig. 1 is a top plan view of the breaker with its actuator or handle shown in on position in full lines and also shown in off position in dotted lines.

Fig. 2 is a section view as if on line 2 2 of Fig. 1 with the parts shown in on position.

Fig. 3 is a View like Fig. 2 but with the parts shown in ofi position.

Fig. 4 is a section view on line 4 4 of Fig. 2.

Fig. 5 is a section view on line 5 5 of Fig. 2.

Fig. 6 is a section view on line 6 6 of Fig. 2.

Fig. '7 is a front view of a yoke part of the device.

Fig. 8 is a view as if from the left of Fig. 7.

Fig. 9 is a view as if from above Fig. 7.

Fig. 10 is a side view of a lower or inner toothed unit or ring member with a handle connected thereto.

Fig. 11 is a View as if from the right of Fig. l0 but with parts shown in section.

Fig. 12 is a bottom plan view of the parts shown in Fig. 11.

Fig. 13 is a section View on line |3-I3 of Fig. 10 but with additional parts shown to illustrate their relative cooperation.

Fig. 14 is a top plan view of the handle as if in the direction of the arrow I4 of Fig. 10.

ring of Fig. 15 as if online l6 lv6, Fig. 17.

Fig. 17 is a view as if from the direction of the arrow l1 of Fig. 15.

Fig.`18 is a section View of the contactor, per se, as if on line l8-l8 of Fig. 19.

Fig. 19 is a view as if in section on line |9-l9 of Fig. 18.

Fig. 20 is a side view of the cover and handle assembly.

Fig. 2l is a side View of the base and the mechanism thereon.

Figs. 22-23 are views like Fig. 2 but showing a three-pole embodiment, in closed circuit position, and in tripped position, respectively, and are sections on line 22 22 and 23-23 of Fig. 24.

Fig. 24 is a top plan view, partly in section, of Fig. 22.

Referring to the drawings, it will be seen that Fig. 21 shows a base 40 at the left end of which is mounted a terminal conductor and binding post 42 having a stationary contact 44 thereon adapted to be engaged by the contact tip 46 of a movable contact or contactor 48, pivotally mounted by means of a loose or lost motion pivot 452 on mounting lugs 54 and constantly urged upwardly or clockwise by a biasing spring 56 and connected by a flexible connector 58 to a bimetal strip 62 permanently fastened to a bracket 64 having its lower end formed as a connector for a terminal and having thereon a binding screw 66.

For controlling the movement of the contactor 48, there is provided a control arrangement, referenced generally A, which will now be described.

A U-shaped frame member 12, shown best in Fig. 4, has thereon a shelf 13 and journals a rotatably movable and axially movable ring or tube 'I4 whose upper end is provided with a plate 15 having a hole 16, shown best in Fig. 13, for receiving a pin 18 projecting downwardly from a plate riveted at 82 to a handle or actuator 84 rotatably mounted, on a vertical axis, in a cup-shaped cover 86 which is adapted to be telescoped down over the base, as shown in Figs. 20 and 21, and to be fastened thereto by screws 88 shown in Fig. 4 to complete the asassembly of the breaker.

Transversely passing through and thus connected to the contactor 48 is a pin 92 which connects the ends or legs of a yoke 94, Fig. 8, to which is fastened a vertical rod 96 telescoped into the ring member or tube 14, Fig. 4, whose lower end is enlarged, as by means of a sleeve l02 fastened thereto by a pin |04 and having teeth |06 on its upper edge. The upper end of tube E4 is provided with the plate 15 which connects to the handle through the pin 18, thus handle 84 and tube 14 may move axially relatively.

The lower edge of the sleeve |02 is notched as shown at |08 to receive a lug ||2 of the yoke 94 so that shoulder ||3 of such notch forms a stop for limiting relative rotation of tube 14 and yoke 94, for purposes later to be described.

The tube 74 is journalled on a vertical axis in the frame 'l2 and its shelf 'I3 to rotate relative to yoke 94 and contactor 48, with such rotation limited by parts ||2||3.

Telescoped around and surrounding the tube 74 and having its upper end disposed Vagainst the upper surface of the frame 12 and its lower end against the upper or toothed edge |06 of the sleeve |02 of tube 14 is another toothed unit or ring |28, the latter having its lower edge formed with teeth |30 .meshing with the teeth of the tube F4 and having its upper end formed with a notched flange |32 having four notches |34 shown best in Fig. 17. These notches cooperate with the upwardly bent end y|36 vof the bimetal strip 82 for releasably latching the toothed sleeved |28 and thus the mechanism as a whole.

Connecting a portion of the frame 12 and a lug of the plate 'l5 is a handle return spring |42.

The circuit from strap 42 to binding post 68 includes the parts 42-444-45-48-58-62-64 Operation When the parts are in the on or closed cir cuit position, as shown in Fig. 2, and with the ange |32 of the outer or upper toothed member or ring |28 releasably latched by lug |36 of bimetal strip 82 seated in a notch |34 of flange |32, and with spring |42 tending to rotate plate 'i5 clockwise, Fig. 13, the parts are held stable in the on position, against the bias of spring 50 by the Vfact that tube 'I4 is prevented from moving by the engagement of its teeth |06 with the teeth |30 on the lower edge of sleeve |28. With sleeve |28 held by latch 62, tube 'i4 can move upwardly only when it can also rotate. Rotation of tube 'f4 to the left, Fig. 4, is prevented by the interengagement of teeth |08 and teeth |80. Rotation of tube T4 to the right, Fig. 2, is prevented by the engagement of lug ||2 of yoke 84 fastened by pin 92 to contactor 48 with the stop ||3 at the end of the notch |08 in the lower edge of sleeve |02 of tube 14.

The stop ||3 at the end of the notch |08 of the lower toothed ring i4 cooperates with the lug |52 of the yoke 84 to form a stop to prevent the lower toothed ring 14 from rotating to the right, Fig. 2, and moving upwardly when the parts are in the circuit closed position and thus, prevents the parts from moving out of the circuit closed position.

Since, for upward movement of contactor 48, the tube T4 must move upwardly and hence must rotate either clockwise or counterclockwise, and `since tube 'i4 is held against rotation, the contactor 48 is held in circuit closing position, against the bias of spring 55 which biases it to open circuit position.

When the handle is rotated clockwise, as shown in Fig. 1, to the ofi position, the connection 'between lit and the tube i4, established through -pin 8 vand plate '|5, causes tube '|4 to rotate to the left, Fig. 2, and thus to cause teeth |08 to clea-r the teeth |30 of sleeve |28, and then to move upwardly, because of the bias of spring 56, and open the circuit.

The initial part of such handle movement will force tube 74 down slightly, as well as to the left, Fig. 2, teeth |30 camming teeth |08 down as they are forced to the left, Fig. 2. Thereafter, teeth |06 will move up between teeth |30. The slight downward movement of tube T4 necessary to permit the teeth |06 to pass by and clear the tips of r.the teeth |30, when the handle is moved to move teeth |06 t0 the left, Fig'. 2, is permitted by the lost motion at 52, the contactor right end moving downwardly a very slight distance, and permit ting tube 14 also to move downwardly a slight distance.

When the handle is returned to the on position from the off position, tube 14 rotates with it, and likewise moves downwardly to move the contactor v48 back to the stationary contact 44 and close the circuit. In the iinal part of the closing stroke, tube T4 will move up slightly 'as Ythe lost motion at 52 is taken up by spring 56.

In the event of an overload, with the parts vin kclosed circuit position, the bimetal 'strip |52 warps downwardly so that its lug `|36 leaves a notch |34 .of flange I3 2 of sleeve |28 and this releases sleeve Automatic relatchz'ng The handle return spring |42 meanwhile exerts its iniluence on the tube l|4 to rotate it and thus, Vcause an additional rotation of the upper toothed sleeve |28 due to the meshing of `the teeth IBS-|30 and, consequently, the upper toothed sleeve |28 will rotate a -ful-l 90 'degrees so as to present another of its four notches |34 to the lug |35 of the bimetal strip |52 which had in the meantime, cooled and returned to position to mesh with one of such notches yoi' the iiange |32 o the upper toothed sleeve |28 and thus, `automatically re-established its latching hold upon the upper toothed sleeve |28. The movement terminates with the parts in the open circuit position and relatched at ILM-|36. The handle meanwhile has moved from the on to the 01T position due to the influence of the handle return spring |42. All the parts are now in the off position.

Trip free with lcircuit closed In the event the handle 84 is held against rotation .during the overload .release movement just ltakes place, and movement of the handle 84 to the open circuit position also takes place, due to the inuence of the handle return spring |42, and relatching at |34|36 also takes place.

lfor this purpose.

However, even if the handle had been held, the upward movement of the tube 14, corresponding to partial rotation of the upper toothed sleeve |28, lis sutlicient to open the circuit and stabilize the parts in the circuit open position.

It will be observed that the trip free action requires longitudinal or axial movement of the tube. 14 relative to the handle 84. This is possible, since the connection between the tube 14 and the handle 84 is established through a pin 18 which can slide vertically in the hole 16 of the plate 15 of tube 14. Thus, relative axial movement of the handle and of thetube is afforded However, relative rotation of handle 84 and tube 14 is not permitted.

Trip free during closing Inthe event an overload takes place near the end of the circuit closing stroke of the handle, or even at any point of the circuit closing stroke of the handle, even under such circumstances, circuit opening movement of the contactor 48 and of the tube 14 will take place. Under these conditions, the bimetal 62 will Warp and release at I34|36 the upper toothed sleeve |28 which is then free to rotate. The tube 14 and the contactor 48 will move upwardly, the upper toothed sleeve |28, however, now moving tothe right,

Fig. .2, as contrasted from the leftward (Fig. 2) direction in which it had traveled during overload release after the circuit had been completely closed.

It will thus be seen that regardless of when the overload release takes place, whether it be during a circuit closing movement or after the com- .pletion of a circuit closing movement, the upper toothed sleeve I 28 is freed by the bimetal latch and being freed, no longer interferes with upward movement of the tube 14 and the contactor 48, regardless of whether the upper toothed sleeve |28 rotates to the left, Fig. 2, as when the release takes place after circuit closing, or to the right, Fig. 2, as when the release takes place during -circuit closing.

Summary.' It will thus be seen that the toothed ring 14 forms part of the handle-contactor assembly, being connected at its upper end to the -handle and at its lower end to the contactor, and

that the toothed sleeve |28, which is releasably held by the latch 62, cooperates with tube 14 t0 form a control arrangement for connecting the latch 62 andthe handle-contactor assembly. In such control arrangement, the inter-action of the teeth determine movement of the tube 'I4 and thus determine movement of the contactor. The latch releasably holds the second ring or sleeve |28 against rotary or lateral motion. When such second ring or sleeve |28 is held, it restrains axial or longitudinal motion of the irst ring or tube 14 except when the latter is given a rotary or lateral motion by the handle to clear the teeth |06 from teeth |3|I.A However, when the second ring or sleeve |28 is released by the warping of latch 62, it no longer interferes with and thus permits axial or longitudinal' motion of the rst -ring or tube 14 without requiring accompanying rotary or lateral motion of such ring or tube 14.

It will also be observed that the contactor 48 connected to the rst member or ring or tube 14 is moved for contact separation when the first member or ring or tube 14 is moved longitudinally or axially, either by actuation from the handle 84 or by release of the second member or sleeve |28 and such motion of the contactor is caused by the biasing spring. 56.Y Y v It may also be noted that the teeth IOS-|30 are formed with oblique surfaces whereby camming co-action of the co-operating teeth IUS- |38 accompanies axial or longitudinal motion of the rst ring or members or tube 14. The teeth :are shown as V-shaped which is the preferred form, but other oblique shapes may also be employed.

It is also noted that tube 14 is of considerably greater length than sleeve |28 and has its teeth formed as an enlarged lowervportion of tube 14. Sleeve or ring |28 is telescoped upon the reduced upper portion of ring or tube 14. Thus the two ends of tube 14 are free to be connected, below to the contactor 48 and above to the actuator or handle 84.

It may also be noted thatthe connection between the tube 14 and the contactor, including the lug H2 of yoke 94 and stop ||3 of tube 14, permits limited relative rotary or lateral motion of tube 14 and the contactor 48. The connection between tube 14 and the actuator or handle 84, including pin 18 and hole 16 of plate 15 of tube 14, permits limited axial movement or longitudinal movement of tube 14 and the actuator or handle 84. f

Referring now to the three-pole embodiment shown in Figs. 22-24, it will be seen that Fig. 22 shows a base 240 at the left end of which are mounted three terminal connectors and binding posts 242 having stationary contacts 244 adapted to be engaged by the contact tips 246 of three movable contactors 248 pivotally mounted at 252 on loose or lost motion pivots like those at 52-54, Fig. 2, and constantly urged upwardly or clockwise by biasing Springs (not shown) like the spring 56 of Fig. 2 and connected individually by ilexible connectors 258 to three electromagnet-coils 262 connected to the three binding screws 266.

A transverse axle 292 insulatedly connects the three contactors 248 so that they operate in unison in response to the control arrangement, referred generally A, which is connected to the laxle 292 and to the handle or actuator 284. The control arrangement A is identical with the control arrangement A shown in the single pole embodiment and includes the tube 14, the plate 15, the pin 18,the yoke 94, the rod 96, the toothed sleeve |02, the toothed ring 28, and the latching flange |32 having four latching notches |34.

The three-pole embodiment includes a latch 236 pivotally mounted at 231 in the frame of the breaker and riveted at 235 to a common latch plate 238 straddling all three poles of the breaker. Loosely hooking around the edge of plate 238 are three armatures 239 for the three magnets 262, these armatures being pivotally mounted in the frame at 240, and normally biased upwardly by springs 24|, but adapted to be pulled down by the magnets 262 on overload.

On an overload in any pole, the magnet thereof will be energized to move its armature 239 down and thus move the common latch plate 238 down to release latch 236 from flange |32 of the control arrangement A and thus trip the breaker,

.as shown in Fig. 23.

Otherwise the action is generally the same as that described for the single pole embodiment.

Now having described the circuit breaker herein disclosed, reference should be had to the claims which follow for a determination of the invention.

We claim:

1. In a circuit breaker, a first assembly of a movable contactor, an actuator, and a -rst 'acta-'css ktoothed ring, Yand 'afsec'ond `assembly of ,a .second toothed ring, and 1a releasable latch for holding it, the two .rings vbeing coaxial, .the vlatch releasably .holding the lsecond .ring Vand thru the vinmesh or out-of-mesh relation of the teeth vof said rings ldetermining rotation and thus Aaxial mine 'contactor movement.

2. In a circuit breaker, a control arrangement comprising ltvvo coaxial rings having meshing teeth and arranged for relative rotary and axial movement, an actuator yand contactor, the rst of `the rings being connected to 'be Aaxially vand rotationallypositionable by said actuator and contactor, and a latch for releasably holding the second ring-against rotary motion.

3. In a circuit breaker, a control arrangement comprising two control members having meshing teeth 'and arranged Afor relative lateral and rotational movement, an `actuator connected -to axially position the rst oi said members, `and a l latch vfor releasably holding the Vsecond member against movement.

4. In a circuit'breaker, a control 4arrangement comprising 'two coaxial rings having meshing teeth and Varranged `for relative rotary and axial movement, an actuator and contacter connected to the rst of the rings, and a latch for releasably holding thesecond ring against rotary motion, the second ring, when held, Arestraining axial motion of the rst ring except when accompanied by rotary movement of the first ring to clear the teeth relatively, -but when the second ring is released, it permits axial motion of the firstring Without requiring accompanying rotary motion of the lirst ring.

5. In a circuit breaker, a control arrangement comprising two control members having meshing teeth and arranged for relative lateral and 'rotational movement, an .actuator connected to the rst of said members, and -a latch for releasably vholding the second member against lateral movemlent, the second member, when held, restraining rotational motion of the rstfmember except when accompanied by lateral movement of the first member caused 'by the actuator movement to clear .the teeth relatively, but 'when' the second member is released,.it vpermits rotational motion of the first member without requiringaccompanying lateral motion of the first member or motonof the actuator.

6. In a circuit breaker, a control arrangement comprising'two control members having meshing teeth and arranged for relative lateral and Lro- `tatona'l movement, an actuator connected to the first of said members, iand .a latch for releasably holding the `second member against lateral movement, the second member, when held,restrain`ing rotational motion of the rstmember exceptwhen accompanied by lateral .movement of kthe rst member caused by the actuator movement to clear the teeth relatively, but when the second member Yis released, it Vpermits rotational motion of the first member without requiring accompanying lateral motion of the first member or -comprising two vcontrolmermbers having meshing teeth and arranged zfor relative lateral and longifil tudinalmovement, an actuator `connected tothe lirst of saidmernb'ers, and a latch for releasably holding the second member against lateral `movement, the second member, 'when held, restraining longitudinal motion of the rst vmember except when accompanied by Ilateral .movement of the :first member caused lby the actuator movement vto clear the teeth relatively, but When the second member is released, it ,permits longitudinal motion of the first member Vwithout requiring accompanying lateral motion of the rst member or motion of the actuator, and a contactor connected to the first member and moved for contact separation by longitudinal motion of the first member, and a 4spring `for biasing the conductor for separation movement when the .contactor and first ml'ember are Vmoved longitudinally, either by the actuator, or by release of the second member.

8. .In .a circuit breaker, a control arrangement comprising two coaxial rings having meshing teeth land arranged .for relative rotary and axial movement, an vactuator and contactor connected to the'rst of the rings, vand a latch forreleasably vholding the second .ring against rotary motion, thesecond ring, when held, restraining axial motion of the first ring except when accompanied by rotary movement lof the rst ring to clear the teeth relatively, but when the second ring is released, .it permits 4axial vmotion of the first ring without requiring .accompanying .rotary .motion of the rst ring, the teeth being formed with oblique surfaces whereby camming coaction of the cooperating teeth vaccompanies axial motion of Athe rstring.

:9. =In a circuit breaker, la control arrangement comprising two control members having meshing teeth .and larranged for .relative lateral 4and longitudinal movement, an yactuator connected to the first of said members, and a latch for releasably holding the second member against lateral movement, the second member, when held, .restraining longitudinal motion-of the rst member except when accompanied by lateral movement of the .first member caused by the actuator panies longitudinal motion yof the rst member.

-10. In a circuit breaker, a control arrangement comprising two control members having meshing teeth and larranged for relative lateral and longitudinal movement, an actuator `connected to the rst of said members, and a latch for releasably holding .the second member against lateral movement, the second member, when held, restraining longitudinal motion of the first member except when accompanied by lateral movement oi the rstmember caused by the actuator .movement to clear the teeth relatively, but when the second ymember is released, it permits longitudinal motion of the rst member without requiring accompanying lateral motion of the rst member or 4motion of the actuator, the teeth being 4formed with oblique vsurfaces whereby camming coaction of the cooperating teeth accompanies longitudinal motion of the irst member, .and a spring loaded contactor connected to the iirstmember and moved for contact .separation by .longitudinal motion of `the first member.

11. In a circuit breaker, a control varrangement aissaose comprising'two control members having meshing teeth and arranged for relative lateral andlongitudinal movement, an actuator connected to the first of saidmembers, anda latch for releasably holding the second member against lateral movement, the second member, when held, restraining longitudinal motion of the rst member except when accompanied by lateral movement of the rst member caused by the actuator movement to clear the teeth relatively, but when the second member is released, it permits longitudinal motion of the first member without requiring accompanying lateral motion of the first member or motion of the actuator, the teeth being formed with oblique surfaces whereby camming coaction of the cooperating teeth accompanics longitudinal motion .of the first member, and a contactor connected to the iirst member and moved for contact separation by longitudinal motion of the rst member, and a spring for biasing the contactor for separation movement when the contactor and first member are moved longitudinally, either by the actuator or by release of the second member.

12. In a circuit breaker, a control arrangement comprising two coaxial rings having meshing teeth and arranged forl relative rotary and axial movement, an actuator and contactor connected to the rst of the rings, and a latch for releasably holding the second ring against rotary motion, the second ring, when held, restraining axial motion of the first ring except when accompanied by rotary movement of the first ring to clear the teeth relatively, but when the second ring is released, it permits .axial motion of the first ring without requiring accompanying rotary motion of the first ring,` and a contactor connected to the first member and' moved for contact separation by longitudinal motion of the first member, and a spring for biasing thefcontactor for separation movement when the contactorand first member are moved longitudinally, either by the actuator, or by release of the second member, the firstring being of considerably greater length than the second and having its teeth formed as an enlarged lower portion thereof, and the second ring being telescoped upon the reduced upper portion of the rst ring, the contactor being connected toV the lower end of the iirst ring and the actuator being connected to the upper end of first ring,

13. In a circuit breaker, a control arrangement comprising two coaxial rings having meshing teeth and arrangedfor relative rotary and axial movement, an actuator and contactor connected to the first of the rings, and a latch for releasably holding the second ringv against rotary motion, the second ring, `when held, restraining axial motion of the iirst ring except'when accompanied by rotary movement of the first-ring to clear the teeth relatively, but when the second ring is released, it permits axial motion of the first ring without requiring accompanying rotary motion of the rst ring, and a contactor connected to the first member and moved for contact separation by longitudinal motion of the first member, and a spring for biasing the contactor for separation movement when the contactor and iirst member are moved longitudinally, either by the actuator, or by release of the second member, the first ring being of considerably greater length than the second and having its teeth formed as an enlarged lower portion thereof, and the second ring being telescoped upon the reduced upper portion of the first ring,

1'0 the contactor being connected to the lower end of the rst ring and the actuator being connected to the upper end of the first ring, the connection between the contactor and first ring permitting limited relative rotary motion of the rst ring and the contactor, and the connection between the actuator and the first ring permitting limited axial movement of the first ring and the actuator.

14. In a circuit breaker, a first member having an enlarged lower portion in the form of a ring, a second member also in the form of a ring and slidably and rotatably telescoped on the `first member and having its lower edge opposing the upper edge of the ring portion of the first member, these opposing edges of the rings having meshing teeth with inclined surfaces, a contactor connected to the lower end of the first member, and an actuator connected to the uppei end of the rst member where the latter projects thru the second member, a iirst spring for biasing said first member to slide and rotate in the second member when the latter is free to rotate, a latch releasably engaging the second ring at successive ones of a plurality of peripherally and circumferentially spaced latch engaging formations thereof to hold said second ring against rotation, a second spring connected to the first member for biasing it to the open circuit position, said second spring operating to rotate said second ring to present another of its latch engaging formations to said latch for automatically relatching said second ring, after a release of said second ring by said latch, and after sliding and rotary movementv of said'rst member in said second ring to open the circuit.

15. In a circuit breaker, a rst member having an enlarged lower portion in the form of a ring, a second member also in the form of a ring and slidably and rotatably telescoped on the first member and having its lower edge opposing the upper edge of the ring portion of the iirst member, these opposing edges of the rings having meshing teeth with inclined surfaces, a contactor connected to the lower end of the first member, andan actuator connected to the upper end of the first member where the latter projects thru the second member, a first spring for biasing said rst member to slide and rotate in the second member when the latter is free'to rotate, a latch releasably engaging the second ring at successive ones of a plurality of peripherally and circumferentially spaced latch engaging formations thereof to hold said second ring against rotation, a second spring connected to the first member for biasing it to the open circuit position, said second spring operating to rotate said second ring to present another of its latch engaging formations to said latch for automatically relatching said second ring, after a. release of said second ring by said latch, and after sliding and rotary movement of said first member in said second ring to open the circuit, the number of latch engaging formations on the second ring equalling the number of pairs of meshing teeth of the two rings.

16. In a circuit breaker, a first member having an enlarged lower portion in the form of a ring, a second member also in the form of a ring and slidably and rotatably telescoped on the rst member and having its lower edge opposing the upper edge of the ring portion of the first member, these opposing edges of the rings having meshing teeth with inclined surfaces, a contactor connected to the lower end of the rst member, and an actuator connected to the upper end of theI lirst member where the latter projects thru the second' member, afirst spring for biasing'said first member to slide andl rotate in the second member when the latter is-freeto rotate, a latch releasably engaging the second ring: at. successive ones of aplurality of peripherally and circumerentiall'yA spaced latch engaging formations thereof to hold said second ring againstlrotation, a second spring connected? to the first member for biasing it to the open circuit position, said secondV spring operating to rotate said secondi ring to present another of its latch engaging formations to said latch for automatically relatching said second ring, after a release of said. second ring by said latch, and after sliding and rotary movement of said first member in saidv second ring to open the circuit, the latch engaging formations of the secondlringt comprising stops projecting radially outwardly from the. second' ring.

17.'. In a circuit breaker, twov members, the first: of which moves for circuit opening, and thev second of which, when held', restrains such movement of the first member, an overload; release latch for holding the second member, the latter having a plurality of' formations for successively engaging said latch, and means for moving. the first member for circuit opening when. the latch. releases said second member, said means operating thru said first member to move the second memberI to present a next succeeding one ofA its formations to saidy latch for automatically relatching the. second member.

18'. In a circuit breaker, two: members, the iirst of which moves. for circuit opening; and the second of which, when held, restrainssuch movementv of the first member, an overload'` release latch for holding the. second. member,l the latter having a plurality of formations for successively engagingV said latch',4 and. means. for moving the. first member` for' circuit: opening when. thev latch releases said second member, said means operating thru. said first member to movey the secondmember: to present a nextfsucseeding: onev of itsr formations to said latchV for automatically relatching the second member, said' members being rotatablyv mounted to rotate on: a. common axis.

19,; Inv a circuit breaker, two: members, the rst` of. which moves for circuitY opening, and. the second of which, when held, restrainsA such movement of the rst member, an overloadl release latch for holding the secondir member; the latter'having a plurality of formations for successively engaging said; latch, and means. for moving the rst member for circuit opening when. the latch releases said second member; said means operating. thru said first member to move the second member to present a next succeeding one ofi its formations to, saidv latch for automatically relatching the second. memben, said members being rotatably mounted to 122 rotate om a common axis andI having cooperating.A meshing teeth with inclined. surfaces.

20'. InA a circuiti breaker, two members, the first of which moves for circut'; opening, andthef second of which, when. held` restrains such movement of the` first member, an overload release latch for holding the second. member, the latter having a. plurality4 of formations for successively engaging saidv latch, and meansfor. moving the first member for:v circuit opening when the latch releases said second member, said means operating thru; said rst member to move the secondv member to present a next succeeding one of its. formationsl to said` latch for automatically rel'atching the second member, said members. being rotatably mounted to rotate on a common axis and having cooperat.- ing meshing teeth with inclined surfaces and a contactor and' an. actuator connected to said -rst member.

21. In a circuit breaker, two coaxial rings, a' contactor, a circuit opening spring, and an actuator. operatively connected to the first ring, an overload release latch' for inhibiting the second ring against rotation, said rings having meshing teeth. with inclinedV surfaces whereby the secondl ring, when. held aga-inst rotation by said latch, restrains axialmovement of thev first ring forl circuit opening, the second ring being freed tol rotate, upon4 latch. release, and thus permitting the rst ring: to` move axially for circuit opening.

22. In a circuit.Y breaker, two coaxial rings, a contactor, a circuit. opening spring,V and an ac.- tuator operativelyA connected to the: rst ring, an overload release-latch for inhibiting the second*V ring against rotation, said rings having meshing teeth with inclined surfaces whereby the second; ring, when held against rotation by said latch, restrains axial. movement of the first ring for. circuit opening, the second ring being freed to rotate, upon latch release, andA thus permitting the rst ring to' move axially for circuit opening, the second.' ring4 rotating in one direction inthe eventl of a latch release during circuit closing movement of the partsV before: the parts have come to rest in circuit closed position, and rotating in the opposite direction in theevent-ofi a latchr release after' the parts have come4 to rest in circuit closed position.

JOHN. A. HERRMANN. ELWOOD T.. PLATZ.

REFERENCES. CITED UNITED STATES PATENTS Name Date Rockwood Mar. 22, 1949 Number 

